Underdrive would make the accessories turn slower which could make them last longer if anything.

 

the motor DOES rev up a little quicker, could be due to a number of things... For one the pulley weighs less than the stock crank pulley, so that's less of strain on the crank... bad for bored engines though.

 

If the life of the water pump, ac, power steering components is not affected, what about their performance? Would the car run hotter? Would the AC not be as cold or blow as hard? Would the steering wheel be harder to turn? Thank you very much for your time!

 

Blue: It's running good with underdrives, don't know if I really notice a difference, I think the motor does rev up a little quicker like everyone is saying. Also, ac is cold as ever, power steering is fine. Only prob. i have is when I'm running my AC, Scan tool, and stereo at the same time, batterie goes low, and if I shut car off, need a jump, so to avoid this, when I'm scanning I leave ac off and radio off. THen as long as I'm not tuning my ECM, I can do whatever as normal.